Sealy PostureTech Oxwich King Size Mattress
The Sealy PostureTech Oxwich Mattress pairs twice-tempered PostureTech springs with a thin polyester fibre layer, which means you get firm, responsive support with only a light cushion on top.
- Extra-firm feel for back sleepers
- Responsive support at pressure points
- Reinforced edges against roll-off
£499
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Sealy PostureTech Oxwich Mattress
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Mattress details
Mattress
Sealy PostureTech Oxwich Mattress
Size
Firmness
Extra Firm
Construction
Depth (cm)
24
Layers
2
Layer Details
Polyester fibre layer
Super soft polyester fibres sit over the spring unit under a traditionally tufted damask cover. They add a light cushion to your movement, though the surface still feels firm.
PostureTech Core Support spring unit
Twice-tempered PostureTech springs form the foundation and give maximum support to pressure points, with EdgeGuard tucked inside. You get firm, responsive support and a reinforced edge against roll-off.
Layer details from crushedvelvetbedstore.co.uk product page, November 2026.
Key benefits
- More room each than a double: You each get 75cm of width, which is 7.5cm more per person than a UK double, so elbows and knees meet a little less often through the night.
- Extra length for taller partners: At 200cm long, the UK king adds 10cm over a UK double, which means feet stay on the mattress rather than hanging off the end.
- Firm edges for an early riser: EdgeGuard reinforcement sits inside the spring unit, so whoever gets up first can sit on the side to dress without the edge sagging beneath them.
- Easier to get in and out of: A supportive edge helps if one of you is recovering from an injury or operation and needs a steady perch before standing up.
- A flat surface across the full width: The extra firm feel and light fibre layer mean neither of you sinks into a dip, which matters more as a shared bed gets wider.
This size suits you if...
You share the bed every night and keep bumping into each other on a UK double, one of you is tall enough to feel the end of a shorter mattress, or you get up at different times and want a sturdy edge to sit on, and you both prefer an extra firm surface.
Consider another size if...
Your bedroom is smaller than our suggested 2.7m x 2.9m for a UK king. We'd recommend the UK double instead, which needs at least 2.6m x 2.8m.
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FAQ's
Is the Sealy Oxwich UK king big enough for two people?
For most couples, yes. The UK king gives you 75cm each, which is 7.5cm more per person than the UK double. If you want a lot more space, perhaps because a dog shares the bed too, the UK super king gives 90cm each.
What size bedroom do I need for a Sealy Oxwich king size mattress?
We suggest at least 2.7m x 2.9m, with 3.2m x 3.2m feeling comfortable once bedside tables and wardrobes are in. New build bedrooms often look roomier empty than furnished, so measure the floor with your furniture in place, then compare the retailers listed on this page.
Is the Oxwich UK king long enough for a tall person?
The UK king is 200cm (6ft 6in) long, 10cm longer than a UK double. If one of you is over six foot, that extra length is often a bigger change than the width, because your feet rest on the mattress instead of the edge.
Should we choose the Sealy Oxwich in a UK king or UK super king?
Both are 200cm long, so the difference is width. The UK super king is 30cm wider, giving 15cm more each, but we suggest at least 3m x 2.9m for it. If your room fits a UK king comfortably and you rarely disturb each other, the UK king is usually enough.
What bedding fits the Sealy Oxwich king size?
Use UK king fitted sheets and a 230 x 220cm king duvet. The mattress is 24cm deep, so check the fitted sheet pocket depth suits it, and remember the Oxwich is double-sided, so the sheet needs to fit well whichever side is facing up.